Integrated access floor system

ABSTRACT

A prefabricated integrated access deck panel includes a bottom flange, one or more structural webs, and an optional top flange. The bottom flange acts as a ceiling soffit, and may include radiant tubing for heating or cooling. The top flange, when present, acts as the floor surface and also supports components of the access floor system. Alternatively, only support rails are used to secure the removable and reconfigurable access floor panels. The webs includes apertures to allow the passage of air and components of the building&#39;s electrical, communication, water, and mechanical systems. Individual deck panels may either be directly interconnected to each other or joined by a common beam to form a diaphragm. Alternative embodiments are disclosed including different deck panel connection and support arrangements, different numbers and configurations for the webs and flanges, and single and dual plenum constructions.

PRIORITY CLAIM

Pursuant to the provisions of 35 U.S.C. Section 119(e), Applicants claim the priority of their U.S. Provisional Patent Application No. 62/211,758, filed Aug. 29, 2015.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates generally to structural floor systems employed in the construction of reinforced concrete, precast concrete, and structural steel buildings. More specifically, the invention pertains to a structural floor system comprising a precast concrete deck integrating a mechanical plenum with an access floor having free air movement capabilities.

2. Description of the Prior Art

A building structure in its most basic form is a series of structural elements designed and arranged to support vertical loads. Vertical loads, such as the weight of the building and the items and occupants in the building, are any forces acting on the building that are the direct result of gravity. Vertical loads are transferred through floors, walls, beams, and posts to the foundation or directly into the ground.

A building must also support lateral loads, acting horizontally upon the structure. One common lateral load is that provided by winds acting on the exterior walls of a building. In addition, at least some of the forces generated by an earthquake have a lateral load component. Lateral loads are transferred to and resisted by the foundation, frame, and walls of a building. Frame components such as beams and columns may be provided with diagonal braces, or they may rely entirely on their inherent stiffness to resist lateral loads.

Conventional modern mid to high rise buildings are predominantly constructed using either structural steel, cast-in-place concrete, or precast concrete construction. In structural steel construction, a metal deck is mounted over steel beams to provide the support for a floor. The metal deck is then filled with a layer of concrete to provide a steel-concrete composite floor system. For the purpose of distributing conditioned air, electrical power, communication lines, and plumbing, those systems are suspended from the steel beams and associated framing. Lastly, a ceiling is typically installed beneath the floor to shield the steel beams and the systems suspended from and attached thereto from view.

In cast-in-place concrete construction, a concrete floor is usually cast as a flat slab, supported by vertically oriented concrete columns that are part of the building's support structure. The underside of the concrete floor is often shrouded by means of a dropped ceiling, concealing air, power, communication, and plumbing systems that are suspended beneath the concrete floor.

Pre-cast concrete floor systems may comprise ribbed concrete panels, manufactured off-site using jigs and forms. After transport to the building site, the concrete panels are assembled over concrete beams. As with the steel construction method discussed above, a thin concrete topping slab is usually cast over the upper side of the panels to integrate the precast panels together structurally. Particularly in an office environment, a ceiling may be suspended from the underside of the concrete panels to conceal mechanical, power, communication and plumbing systems.

In all of the floor systems discussed thus far, the mechanical, power, communication and plumbing systems are located below a structural floor slab. In contrast, in an access floor system, a floor is built on top of a structural deck, defining a cavity or volume between the floor and the structural deck. The access floor is comprised of a series of square or rectangular floor panels that are maintained approximately six (6) to eighteen (18) inches above the structural floor slab by pedestals. The floor panels are detachably affixed to the pedestals, so they may be removed as needed. Access floor systems are also designed to transfer lateral loads to the structural deck to avoid system racking and to provide restraint to seismic forces.

The cavity provided by an access floor system accommodates mechanical, power, communication and plumbing systems. Since the floor panels may be removed, these service systems are readily accessible, and they may be modified and reconfigured to suit relocation and expansion needs in the office or work space above.

Another advantage of access floor systems is that the cavity can also be utilized for underfloor ventilation. When its cavity is also charged with conditioned air, an access floor system is termed a plenum. Underfloor ventilation through the plenum provides flexibility in work area arrangements, and provides performance advantages over ducted ventilation systems.

A structural floor typically serves two purposes as a building component. First, the structural floor must safely support its own weight in addition to the weight of occupants, furniture, and equipment supported by the floor surface. Second, the structural floor must interconnect associated lateral elements of a building together, so that lateral forces in the floor will be distributed and transferred to the lateral resisting elements in the building. In the present field of art, such a floor system is commonly referred to as a “diaphragm”, a term structural engineers use when designing lateral load paths through the floor system.

Structural floor systems made from precast concrete fall into two major categories. The first more conventional floor system is a topped precast diaphragm, in which a plurality of individual precast units are arranged together in coplanar relationship and a concrete slab is poured over the assemblage. In that way, the individual units are made to act as a single diaphragm.

The second structural floor system is termed an untopped or a pretopped diaphragm system. In this arrangement, the precast floor panels are interconnected with welded or mechanical connections to achieve a structurally integrated, continuous diaphragm. Historically, pretopped diaphragm construction methods have been limited to buildings not located within a region having high seismic activity. However, recent research performed by Ren at Lehigh University advocates a reliable means of extending the use of pretopped precast diaphragms to high seismic regions. [See, Ren, Ruirui, Seismic Performance Evaluation and Effective Design of Precast Concrete Diaphragm Connections, (2011) Theses and Dissertations, Paper 1307].

Finrock Industries, Inc., of Apopka, Fla., has developed a Dual Panel Composite Truss Apparatus, shown in U.S. Pat. No. 8,667,755. The apparatus comprises a composite truss having a pair of spaced precast concrete slabs, integrated with structurally supporting end bearing trusses. The composite truss is for use as the floor or ceiling in a building construction, as shown in FIG. 5 of the '755 patent. Lift tubes are incorporated into the end bearing trusses to allow the composite truss to be lifted by threadably coupling lifting cables to the tubes. This system does not integrate access flooring into the top slab of the composite truss.

Other prior art floor systems are described in an article entitled “Review Of Existing Precast Concrete Gravity Load Floor Framing Systems”, included in the March-April 1995 Issue of the PCI Journal, on pages 52-68. In this review, some nineteen precast structural floor systems suitable for office building construction are shown in drawings and photographs and discussed by the authors.

However, the need still exists for a prefabricated integrated access deck panel which combines a flexible floor space construction with a plenum and a ceiling soffit.

The need also exists for an access floor system and a ceiling soffit which are integrated and interconnected by means of a structural web.

The need further exists for a system comprising a plurality of integrated access deck panels which may be interconnected to provide a structural diaphragm for building construction.

The need further exists for a prefabricated integrated access deck panel defining a cavity between an upper access floor system and a lower ceiling soffit or flange, that may be adapted to form a single plenum or a dual plenum, to accommodate mechanical systems.

These and other objects and features of the invention herein will become apparent from the drawings and the written specification which follow.

SUMMARY OF THE INVENTION

The invention comprises a prefabricated integrated access deck panel having a bottom flange, one or more structural webs, and an optional top flange. The bottom flange acts as a ceiling soffit for the floor below, and may be cast with custom recesses or decorative patterns on its lower side to accommodate lighting or architectural features. The bottom flange may also be cast with circuits of radiant tubing passing through it, for heating or cooling.

The top flange is used in some of the embodiments, and is not needed in other embodiments. When the top flange is used, it acts both as a portion of the floor surface and also to support components of the associated access floor system. Alternatively, when the top flange is not present, only support rails are used to secure the removable and reconfigurable access floor panels.

The webs include apertures to allow the passage of air and components of the building's electrical, communication, water, and mechanical systems.

Individual deck panels may either be directly interconnected to each other or joined by an interior structural beam extending between them, to form a diaphragm. Exterior structural beams support the portions of the deck panels at the periphery of the building.

Alternative embodiments for the deck panels are disclosed including different deck panel connection and support arrangements, different numbers and configurations for the structural webs and the flanges, and single and dual plenum constructions.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing a plurality of integrated access deck panels assembled with support members of a building framework, upper portions of certain of the panels being removed to show internal structural features;

FIG. 2 is a fragmentary close-up perspective view of a portion of an integrated access deck panel, showing a pair of opposing webs with apertures passing therethrough, a bottom flange and an optional top flange;

FIG. 3 is a perspective view showing a floor support rail for use with the access deck panels;

FIG. 4 is a fragmentary perspective view of a pair of access deck panels with their respective bottom flanges being joined and including optional radiant tubing for heating and cooling;

FIG. 5 is a fragmentary perspective view of an interior beam provided with a ledge supporting an integrated access deck panel;

FIG. 6 is a fragmentary cross-sectional view, taken on the line 6-6 in FIG. 1, showing an interior beam using a combination of hangers and rebar to support deck panels, in lieu of ledges;

FIG. 7 is a fragmentary cross-sectional view showing another deck panel support arrangement, in which the interior beam includes ledges and the bottom flanges of the deck panels includes notches;

FIG. 8 is a fragmentary cross-sectional view showing yet another deck panel support arrangement, in which the interior beam includes ledges and shear lugs, ledge connectors, and grout interconnect the bottom flanges with the ledges;

FIG. 9 is a fragmentary cross-sectional view showing another arrangement for interconnecting two deck panels, including a keyed joint common with the abutting bottom flanges in two deck panels;

FIG. 10 is a fragmentary cross-sectional view of a deck panel having two opposing webs, each including a respective top flange having a “T” configuration;

FIG. 11 is a view as in FIG. 10, but with each top flange having a horizontal portion directed away from the other;

FIG. 12 is a fragmentary cross-sectional view of a deck panel having two outside connection top flanges and an intermediate top flange having a “T” configuration;

FIG. 13 is a view as in FIG. 12, but with two intermediate top flanges having a “T” configuration;

FIG. 14 is a fragmentary cross-sectional view of a deck panel having outwardly diverging webs each capped with outwardly directed top flanges;

FIG. 15 is a fragmentary cross-sectional view of a deck panel with a single web and a top flange having a “T” configuration;

FIG. 16 is a fragmentary cross-sectional view of a deck panel with a pair of upwardly tapered webs and a bottom flange with support pedestals, a support rail running continuously over the upper ends of the tapered webs;

FIG. 17 is a fragmentary cross-sectional view of a deck panel with a pair of steel webs provided with cross-bracing, a support rail and associated access panels forming the floor supported by the webs; and,

FIG. 18 is view as in FIG. 16, but with a divider deck interconnected to an intermediate portion of the webs and a deck panel arranged in spaced relation above the divider deck, thereby defining an upper supply plenum and a lower return plenum.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Turning now to the drawings, and in particular FIGS. 1 and 2, an integrated access deck panel 11 is shown. Preferably deck panels 11 are manufactured at a facility off-site from a main building site. At the manufacturing facility, individual panels 11 are pre-cast from concrete into an integrated structure, including whatever customized structural or architectural features are called for. After the panels 11 have cured, they are transported to the building site where they can be assembled and joined with other building structures and assemblies. This manner of construction, involving prefabrication of major structural components off-site, has been proven to save labor costs and to accelerate construction speed, compared to conventional methods of construction.

The access deck panel 11 includes a bottom flange 12, one or more structural webs 13, and an optional top flange 14. The bottom flange 12 acts as a ceiling soffit for the floor below, and its underside may include decorative designs, architectural features, or structural accommodations for lighting fixtures. As shown in FIGS. 4 and 5, the bottom flange 12 may also be cast with radiant tubing 16 for heating and/or cooling.

The optional top flange 14 is used on some of the embodiments of the deck panel 11. As shown in FIGS. 1 and 2, where a top flange 14 is used, its upper surface provides a portion of the overall floor surface. Top flange 14 also supports certain components of the access floor system. In the embodiment of deck panel 11 shown in FIG. 2, the two top flanges 14 include opposing inner edges 17 and remote outer portions 18. Inner edges 17 are provided with respective receiver means 19. Outer portions 18 are also provided with respective receiver means 19. In this embodiment, receiver means 19 comprises channels cast into flanges 14, providing a recessed load bearing surface. Other equivalent arrangements, including slots, pins, or other mechanical fasteners would work equally well for receiver means 19.

The purpose of receiver means 19 is to provide a convenient structure to accept and sustain a plurality of support rails 21. The example of support rail 21 illustrated in FIG. 3, comprises a fabricated structural steel element. The specific configuration and structural design of rail 21 is dependent upon the size and type of floor panel 22 it must support, as well as the span between the end supports. Rail 21 is fabricated from an upper steel tube 23 and a lower steel tube 24. Tube 23 and tube 24 are welded to a center connector plate 26 and end connector plates 27. Threaded apertures 28 are provided in plate 26 and plates 27 to secure hardware for mounting floor panels 22 to the support rails 21.

Typically, floor panels 22 are 2′×2′ square, although they may be any convenient size and or configuration. Floor panels 22 also include reinforcement ribs or other structures (not shown) on their underside, to provide a strong and unyielding floor support. In the present application, the square floor panels 22 have a bore in each corner to pass threaded mounting bolts. These bolts, in turn, are screwed into apertures 28 when the floor panels 22 are mounted and assembled as part of the access floor system.

FIG. 4 shows a bottom flange edge connection, between two deck panels 11. Flange connectors 29, including respective weld plates 31, are embedded into bottom flanges 12, when they are cast. As shown in FIG. 2, only weld plates 31 remain exposed after the casting process is complete. At the building site, where deck panels 11 are arranged in side-to-side relation, a flange joint 32 is exists. Abutting weld plates 31 from each deck panel 11 are welded together, forming a structural union between panels 11 along the flange joint 32.

Also evident in FIG. 4 are apertures 33, arranged along each structural web 13. Apertures 33 are provided for two reasons: (1) to allow the direct flow of heating or cooling air under floor panels 22; and, (2) to define passageways for the power, communication, plumbing, and mechanical systems used in building construction. As described in more detail below, the combination of the integrated access floor system with the apertures 33, allows relatively quick and easy initial deployment of these systems. In addition, later modifications and rearrangements of the systems are easily implemented, as changed circumstances dictate.

FIG. 1 illustrates an example of a building floor system 34 utilizing a plurality of the integrated access deck panels 11 of the present invention. In addition to deck panels 11, floor system 34 includes an interior beam 36 and peripheral exterior beams 37. Interior beam 36 and exterior beams 37 are supported by vertical posts 38, arranged at the corners and along the sides of the floor system 34. Structural shear walls 39 are also included, to resist lateral forces imposed on the building into which the floor system 34 is incorporated.

The left hand portion of the floor system 34 depicted in FIG. 1, shows the interior structure of deck panels 11, with the top flanges 14 and the support rails 21 exposed. The corner cut-away portion in the intermediate section of FIG. 1, shows the upper surfaces of top flanges 14 and the floor panels 22 installed over the support rails 21. The remainder of the floor system 34 illustrated in FIG. 1, shows the floor covering 41, typically carpet, completely covering the deck panels 11 and their components.

Turning now to FIG. 5, a detail of the structural interconnections between an interior beam 36 and a pair of deck panels 11 is shown. Interior beam 36 is provided with opposing ledges 42, along its lower portion. Flange connectors 29 are cast into beam 36 along its vertical wall portions, immediately above ledges 42. Weld plates 31, connected to flange connectors 29, lie exposed in the wall portions. Corresponding flange connectors 29 and weld plates 31 have also been cast into adjacent end portions of bottom flange 12. After the end portion of bottom flange 12 has been positioned over a ledge 42, the two adjacent weld plates 29 are welded. And, as has previously been explained, the adjacent weld plates 29 in the flange joint 32 are also welded at this time, joining the two deck panels 11.

It should also be noted that exterior beams 37 are also provided with ledges 42, but only along their inner facing lower portions. Identical attachment means are employed, using the flange connectors 29 and the weld plates 31, to interconnect the other ends of the deck panels 11 to the exterior beams 37. Those deck panels 11 that have exterior sides, positioned along an exterior beam 37, are similarly provided with flange connectors 29 and the weld plates 31. These exterior sides rest over ledges 42 and the weld plates 31 above the ledges 42 and the weld plates 31 along the exterior sides are welded together. This process is continued, until all of the deck panels 11 are installed and fully interconnected with interior beams 36 and exterior beams 37, and fully interconnected between themselves as well.

Alternative beam configurations and connections may also be used to practice the present invention. For example, FIG. 6 shows a cross-sectional view taken through a rectangular beam 36 without a ledge. Pockets 43 are notched into the upper, opposing edges of beam 36. Steel hangers 44 extend from structural web 13, and are installed within a respective pocket 43. After deck panel 11 is finally positioned, pockets 43 are filled with grout 46 to provided a flush floor surface between beam 36 and the upper surface of top flange 14.

The combination of the hangers 44 and the pockets 43 is effective to support the weight of the floor structure and any occupant loading. However, additional connectors between the bottom flange 12 and the beam 36 are necessary to transfer lateral loads. For that purpose, a section of rebar 47, provided with threaded couplers 48 at each end thereof, is cast transversely into the beam 36. The bottom flange 12 of the deck panel 11, is cast with inverted rebar anchors 49, having a portion extending upwardly from the upper surface of flange 12. A splice is made by threading a headed bolt 51 into the coupler 48, and by threading steel reinforcement corner bars 52 through an anchor 49. The splice is completed by covering the exposed connectors with concrete or grout 53.

Yet another variation in the construction of interior beam 36 is illustrated in FIG. 7. In this arrangement, the bottom of beam 36 is provided with a support foot 54 having protruding ledges 56. The bottom flange 12 and a small portion of web 13 of each deck panel 11 includes a notch 57 to accommodate a respective ledge 56. The web 13 is set directly on a bearing pad 58 that rests on the ledge 56. A headed rod 59 is cast within bottom flange 12, and has a portion which projects horizontally through a keyed joint 61. When the deck panel 11 is set on the beam 36, the headed rods 59 set into ribbed slots 62 that align with the rods. A backer rod and caulk 63 is used to seal the joint, and the splice is completed by filling the keyed joint 61 and the ribbed slots 62 with grout 64.

FIG. 8 depicts another alternative construction for interior beam 36. This construction also uses a support foot 54 having protruding ledges 56, as does the construction shown in FIG. 7. Shear lugs 66 replace flange connectors 29 and weld plates 31 to transfer the lateral diaphragm forces from the deck panel 11 to the beam 36. The shear lugs 66 are threaded into couplers cast into the ledges 56. Circular pockets 67 are cast into the bottom flange 12 to accommodate the shaft and head of the shear lugs 66. In the field, the deck panel 11 is set on bearing pads 58 located under the structural web 13. The connection is completed by filling the circular pockets 67 with grout 64.

Another method of interconnecting adjacent deck panels 11 is shown in FIG. 9. A keyed joint 68 is formed into the bottom flange 12 of each deck panel 11. A double-ended headed rebar dowel 69 is set into a ribbed slot 71. Either a backer rod or caulk 63 is used to seal the flange joint 32. Lastly, grout 64 is used to fill the keyed joint 68 and the ribbed slot 71.

In FIG. 10, a deck panel 11 is shown which includes first and second structural webs 13 arranged in parallel spaced relation on bottom flange 12. The first structural web 13 interconnects the bottom flange 12 with a first top flange 14. The second structural web 13 interconnects the bottom flange 12 with a second top flange 14. The first and second top flanges have opposing inner edges 72 and 73, each being provided with respective receiver means 19. A support rail 21 spans and is supported by the receiver means 19. Access floor panels 22 are secured to support rail 21, and form a co-planar floor surface with the first and second top flanges 14. The first and second top flanges 14 further include outer portions 74 and 76, also provided with respective receiver means 19. In this manner, the additional support rails 21 and the associated floor panels 22 of adjacent deck panels 11 may be supported and functionally integrated.

FIG. 11 shows a deck panel 11 which is very similar to that shown in FIG. 10. The principal difference is that the top flanges 14 do no have a “T” configuration, but rather only include the respective outer portions 74 and 76. Opposing inner edges 72 and 73, and the outer portions 74 and 76, all include respective receiver means 19 to accept support rails 21.

Another variation in the construction of a deck panel 11 is depicted in FIG. 12. Deck panel 11 includes first, second, and third structural webs 13 arranged in parallel spaced relation on the bottom flange 12. The first structural web 13 interconnects bottom flange 12 with a first top flange 14. The second structural web 13 interconnects the bottom flange 12 with a second top flange 14. The third structural web 13 interconnects the bottom flange 12 with a third top flange 14. The first and second top flanges 14 have respectively opposing inner edges 77 and 78, each provided with respective receiver means 19. A pair of access floor panels 22, resting on a support rail 21, forms a co-planar floor surface with first and second top flanges 14. The second and third top flanges 14 have respectively opposing inner edges 79 and 81, each provided with respective receiver means 19. A pair of access floor panels 22, resting on a support rail 21, forms a co-planar floor surface with second and third top flanges 14. Grout 64 is placed within recesses in top flanges 14 to seal the joint between adjacent deck panels 11 and to continue the co-planar floor surface.

The deck panel 11 shown in FIG. 13 includes a bottom flange 12, a plurality of access floor panels 22, a plurality of access floor panel support rails 21, and a plurality of top flanges 14 parallel to and in spaced relation from bottom flange 12 defining a cavity 82 therebetween. The upper sides of top flanges 14 form a floor surface, and further include respective receiver means 19 for engaging support rails 21 and maintaining them in horizontal relation. Access floor panels 22 rest on support rails 21 and form a co-planar floor surface with the upper surface of top flanges 14. A plurality of structural webs 13 is provided, each interconnecting bottom flange 12 with a respective one of the top flanges 14. Each one of the webs 13 include apertures 33 to allow for the passage of air and components of a electrical, communication, plumbing, and power systems in and through cavity 82.

In FIG. 14, the deck panel 11 has a wider center profile, and no access floor panels 22 are used between adjacent deck panels 11. In other words, if additional deck panels 11 are positioned along side the single panel shown, the outer ends of bottom flange 12 and the outer ends of top flange 14 would be connected together using one of the methods previously described. This would provide a continuous co-planar floor surface provided by the upper surfaces of the connected top flanges 14. This arrangement allows the entire floor system to be prefabricated, reducing the amount of field work required to complete the access floor system. Note that the structural webs 13 are angulated upwardly and outwardly, rather than being perpendicular to bottom flange 12 and parallel with respect to each other as in other embodiments. In addition, support rail 21 is more extended in length, and is therefore able to accommodate four access floor panels 22 across its span.

The most basic configuration for a deck panel 11 is shown in FIG. 15. This construction employs a single structural web 13 and a single top flange 14. As with the other embodiments, web 13 includes an aperture 33, and top flange 14 includes receiver means 19 to accommodate the ends of support rails 21. This construction for deck panels 11 could be used to reduce production labor, or the weight of the floor components.

FIG. 16 illustrates a deck panel 11 having first and second upwardly tapering structural webs 13, extending perpendicularly and upwardly from a common bottom flange 12. The webs 13 do not include the top flanges 14, as used in the other embodiments. This simplifies production of the deck panels 11. The support rail 21 is run continuously over the upper ends of the first and second structural webs 13. A plurality of access floor panels 22 rest on the support rail 21, forming a co-planar floor surface. The floor panels 22 and the bottom flange 12 define a cavity 82 therebetween. The first and second webs 13 include apertures 33 to allow for the passage of air and components of a electrical, communication, plumbing, and power systems in and through the cavity 82.

Another embodiment of deck panel 11, shown in FIG. 17, is comprised of a combination of steel members and concrete members. The bottom flange 12 is affixed to first and second structural steel webs 83 using cast concrete anchors (not shown) welded to the bottoms of the webs 83. The structural steel webs 83 are in the form of I-beams, and they include apertures 33, as do the concrete webs 13 described previously. Cross-braces 84 extend from an upper end of the first structural steel web 83 to a lower end of the second structural steel web 83, and from an upper end of the second structural steel web 83 to a lower end of the first structural steel web 83. One or more support rails 21 extend across the upper ends of the first and second structural steel webs 83. A plurality of access floor panels 22 rest on the support rails 21, and forming a co-planar floor surface. The floor panels 22 and the bottom flange 12 define a cavity 82 therebetween. The apertures 33 in the first and second structural steel webs 83 allow for the passage of air and components of a electrical, communication, plumbing, and power systems in and through cavity 82.

Lastly, FIG. 18 teaches a deck panel 11 having dual plenum chambers. In this construction, a first structural web 13 and a second structural web 13 extend perpendicularly and upwardly from the bottom flange 12. The first and second webs 13 include apertures 33 in their lower portions, to allow for the passage of air and the components of a electrical, communication, plumbing, and power systems. A divider deck 86 and a divider deck support 87 are provided between webs 13, parallel to and in spaced relation from the flange 12 defining a lower air return plenum 88. A plurality of vertically adjustable pedestals 89 is provided, with their lower ends resting on the upper surface of divider deck 86. The upper ends of the pedestals 89, include mounting brackets 91 to which respective access floor panels 22 are directly attached, forming a co-planar floor surface. An upper air supply plenum 92 is thereby defined between the divider deck 86 and the floor panels 22. In this manner, conditioned air is provided through upper air supply plenum 92 to the working space, and return air is drawn from the working space and routed to the heating or air conditioning unit through lower air return plenum 88. Components of electrical, communication, plumbing, and power systems may alternatively be passed through upper air supply plenum 92, as well. 

What is claimed is:
 1. A prefabricated integrated access deck panel comprising: a. a bottom flange; b. at least one access floor panel; c. a plurality of access floor panel support rails; d. a top flange parallel to and in spaced relation from said bottom flange defining a cavity therebetween, said top flange forming a floor surface and further including receiver means for engaging said support rails and maintaining them in horizontal relation, said floor panel resting on said support rails and forming a co-planar floor surface with said top flange; and, e. at least one structural web interconnecting said bottom flange and said top flange, said web including apertures to allow for the passage of air and components of a electrical, communication, plumbing, and power systems in said cavity.
 2. A deck panel as in claim 1 in which said bottom flange comprises a ceiling soffit.
 3. A deck panel as in claim 2 in which said bottom flange includes radiant tubing for heating or cooling.
 4. A deck panel as in claim 1 in which said receiver means comprises at least one channel cast in said top flange providing a recessed bearing location for said support rails.
 5. A deck panel as in claim 1 further including a second said deck panel, in which said webs of said first and second said deck panels are arranged in parallel, spaced relation, and in which said plurality of support rails spans said receiver means of said first and second deck panels, said bottom flanges of said first and second deck panels being joined by flange connectors located along respective adjacent edges.
 6. A deck panel as in claim 1 further including an interior beam, said interior beam including a ledge along a lower edge and a lateral face above said lower edge, and in which said web has one end in abutment with said lateral face and in which one edge of said bottom flange rests over said ledge, and further including means for interconnecting said one edge of said bottom flange with said interior beam.
 7. A deck panel as in claim 1 further including an exterior beam, said exterior beam including a ledge along a lower edge and a lateral face above said lower edge, and in which said web has another end in abutment with said lateral face of said exterior beam and in which the other edge of said bottom flange rests over said ledge of said exterior beam, and further including means for interconnecting said other edge of said bottom flange with said exterior beam.
 8. A deck panel as in claim 1 including first and second structural webs, said first and second webs being arranged in parallel spaced relation on said bottom flange, and in which said first web interconnects said bottom flange with a first top flange and said second web interconnects said bottom flange with a second top flange, said first and second top flanges having opposing inner edges provided with respective said receiver means and in which said access floor panel forms a co-planar floor surface with said first and second top flanges.
 9. A deck panel as in claim 9 in which said first and second top flanges further include outer portions provided with respective said receiver means.
 10. A deck panel as in claim 1 including first, second, and third structural webs, said first, second, and third webs being arranged in parallel spaced relation on said bottom flange, and in which said first web interconnects said bottom flange with a first top flange, said second web interconnects said bottom flange with a second top flange, and said third web interconnects said bottom flange with a third top flange, said first and second top flanges having respectively opposing inner edges provided with respective said receiver means and in which a first said access floor panel forms a co-planar floor surface with said first and second top flanges, and in which said second and third top flanges having respectively opposing inner edges provided with respective said receiver means and in which a second said access floor panel forms a co-planar floor surface with said second and third top flanges.
 11. A deck panel as in claim 1 in which said bottom flange, said top flange, and said structural web are pre-fabricated from concrete.
 12. A prefabricated integrated access deck panel comprising: a. a bottom flange; b. a plurality of access floor panels; c. a plurality of access floor panel support rails; d. a plurality of top flanges parallel to and in spaced relation from said bottom flange defining a cavity therebetween, said top flanges forming a floor surface and further including respective receiver means for engaging said support rails and maintaining them in horizontal relation, said access floor panels resting on said support rails and forming a co-planar floor surface with said top flanges; and, e. a plurality of structural webs each interconnecting said bottom flange with a respective one of said top flanges, said plurality of webs including apertures to allow for the passage of air and components of a electrical, communication, plumbing, and power systems in said cavity.
 13. A deck panel as in claim 12 in which said bottom flange, said top flanges, and said structural webs are pre-fabricated from concrete.
 14. A deck panel as in claim 12 in which said access floor panels are detachably affixed to said support rails.
 15. A prefabricated integrated access deck panel comprising: a. a bottom flange; b. a plurality of access floor panels; c. a plurality of access floor panel support rails; and, d. a first structural web and a second structural web, said first and second webs extending perpendicularly and upwardly from said bottom flange to respective upper ends, said plurality of access floor panel support rails extending across said upper ends of said first and second webs, said floor panels resting on said support rails and forming a co-planar floor surface, said floor panels and said bottom flange defining a cavity therebetween, said first and second webs including apertures to allow for the passage of air and components of a electrical, communication, plumbing, and power systems in said cavity.
 16. An access deck panel as in claim 15 in which said bottom flange and said first and second structural webs are pre-fabricated from concrete.
 17. An access deck panel as in claim 15 in which said bottom flange is pre-fabricated from concrete and said first and second structural webs are manufactured from steel beams which are attached to concrete anchors in said bottom flange.
 18. An access deck panel as in claim 17 including cross-braces extending from said upper end of of said first structural web to a lower end of said second structural web, and from said upper end of said second structural web to a lower end of said first structural web.
 19. A prefabricated integrated access deck panel comprising: a. a bottom flange; b. a plurality of access floor panels; c. a plurality of pedestals each of said pedestals having a lower end and an upper end; d. a first structural web and a second structural web, said first and second webs extending perpendicularly and upwardly from said bottom flange, said first and second webs including apertures to allow for the passage of air and components of a electrical, communication, plumbing, and power systems; and, e. a divider deck between said bottom flange and said floor panels defining a lower air return chamber and an upper air supply chamber, said divider deck being supported by said first and second webs in parallel relation to said bottom flange and said floor panels, said lower ends of said pedestals resting on an upper surface of said divider deck, and said floor panels resting on said upper ends of each of said pedestals forming a co-planar floor surface.
 20. An integrated access deck panel as in claim 19 in which said divider deck is supported by said first and second webs above said apertures to allow free movement of air through said lower air return chamber, and said divider deck is sufficiently spaced from said floor panels to allow free movement of air through said upper air supply chamber. 